Re: [Intel-gfx] [PATCH V2] drm/i915/gt: Hold RPM wakelock during PXP suspend

Daniele Ceraolo Spurio
2021-11-09T21:35:26Z

On 11/8/2021 10:32 PM, Jani Nikula wrote:
> On Tue, 09 Nov 2021, "Surendrakumar Upadhyay, TejaskumarX" <tejaskumarx.surendrakumar.upadhyay@intel.com> wrote:
>>> -----Original Message-----
>>> From: Jani Nikula <jani.nikula@linux.intel.com>
>>> Sent: 09 November 2021 00:37
>>> To: Surendrakumar Upadhyay, TejaskumarX
>>> <tejaskumarx.surendrakumar.upadhyay@intel.com>; intel-
>>> gfx@lists.freedesktop.org
>>> Subject: Re: [Intel-gfx] [PATCH V2] drm/i915/gt: Hold RPM wakelock during
>>> PXP suspend
>>>
>>> On Mon, 08 Nov 2021, Tejas Upadhyay
>>> <tejaskumarx.surendrakumar.upadhyay@intel.com> wrote:
>>>> selftest --r live shows failure in suspend tests when RPM wakelock is
>>>> not acquired during suspend.
>>>>
>>>> This changes addresses below error :
>>>> <4> [154.177535] RPM wakelock ref not held during HW access <4>
>>>> [154.177575] WARNING: CPU: 4 PID: 5772 at
>>>> drivers/gpu/drm/i915/intel_runtime_pm.h:113
>>>> fwtable_write32+0x240/0x320 [i915]
>>>> <4> [154.177974] Modules linked in: i915(+) vgem drm_shmem_helper fuse
>>>> snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic
>>>> ledtrig_audio mei_hdcp mei_pxp x86_pkg_temp_thermal coretemp
>>>> crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_intel_dspcfg
>>>> snd_hda_codec snd_hwdep igc snd_hda_core ttm mei_me ptp snd_pcm
>>>> prime_numbers mei i2c_i801 pps_core i2c_smbus intel_lpss_pci btusb
>>>> btrtl btbcm btintel bluetooth ecdh_generic ecc [last unloaded: i915]
>>>> <4> [154.178143] CPU: 4 PID: 5772 Comm: i915_selftest Tainted: G
>>>> U 5.15.0-rc6-CI-Patchwork_21432+ #1
>>>> <4> [154.178154] Hardware name: ASUS System Product Name/TUF
>>> GAMING
>>>> Z590-PLUS WIFI, BIOS 0811 04/06/2021 <4> [154.178160] RIP:
>>>> 0010:fwtable_write32+0x240/0x320 [i915] <4> [154.178604] Code: 15 7b
>>>> e1 0f 0b e9 34 fe ff ff 80 3d a9 89 31
>>>> 00 00 0f 85 31 fe ff ff 48 c7 c7 88 9e 4f a0 c6 05 95 89 31 00 01 e8
>>>> c0 15 7b e1 <0f> 0b e9 17 fe ff ff 8b 05 0f 83 58 e2 85 c0 0f 85 8d
>>>> 00 00 00 48
>>>> <4> [154.178614] RSP: 0018:ffffc900016279f0 EFLAGS: 00010286 <4>
>>>> [154.178626] RAX: 0000000000000000 RBX: ffff888204fe0ee0
>>>> RCX: 0000000000000001
>>>> <4> [154.178634] RDX: 0000000080000001 RSI: ffffffff823142b5
>>>> RDI: 00000000ffffffff
>>>> <4> [154.178641] RBP: 00000000000320f0 R08: 0000000000000000
>>>> R09: c0000000ffffcd5a
>>>> <4> [154.178647] R10: 00000000000f8c90 R11: ffffc90001627808
>>>> R12: 0000000000000000
>>>> <4> [154.178654] R13: 0000000040000000 R14: ffffffffa04d12e0
>>>> R15: 0000000000000000
>>>> <4> [154.178660] FS: 00007f7390aa4c00(0000) GS:ffff88844f000000(0000)
>>>> knlGS:0000000000000000
>>>> <4> [154.178669] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4>
>>>> [154.178675] CR2: 000055bc40595028 CR3: 0000000204474005
>>>> CR4: 0000000000770ee0
>>>> <4> [154.178682] PKRU: 55555554
>>>> <4> [154.178687] Call Trace:
>>>> <4> [154.178706] intel_pxp_fini_hw+0x23/0x30 [i915] <4> [154.179284]
>>>> intel_pxp_suspend+0x1f/0x30 [i915] <4> [154.179807]
>>>> live_gt_resume+0x5b/0x90 [i915]
>>>>
>>>> Changes since V1 :
>>>> - split the HW access parts in gt_suspend_late - Daniele
>>>> - Remove default PXP configs
>>>>
>>>> Signed-off-by: Tejas Upadhyay
>>>> <tejaskumarx.surendrakumar.upadhyay@intel.com>
>>>> ---
>>>> drivers/gpu/drm/i915/gt/intel_gt_pm.c | 7 ++++---
>>>> drivers/gpu/drm/i915/pxp/intel_pxp_pm.c | 15 ++++++++++++---
>>>> drivers/gpu/drm/i915/pxp/intel_pxp_pm.h | 18 ++++++++++++++++--
>>>> 3 files changed, 32 insertions(+), 8 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.c
>>>> b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
>>>> index b4a8594bc46c..d4029de1c80d 100644
>>>> --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.c
>>>> +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
>>>> @@ -303,7 +303,7 @@ void intel_gt_suspend_prepare(struct intel_gt *gt)
>>>> user_forcewake(gt, true);
>>>> wait_for_suspend(gt);
>>>>
>>>> - intel_pxp_suspend(&gt->pxp, false);
>>>> + intel_pxp_suspend_prepare(&gt->pxp, false);
>>>> }
>>>>
>>>> static suspend_state_t pm_suspend_target(void) @@ -328,6 +328,7 @@
>>>> void intel_gt_suspend_late(struct intel_gt *gt)
>>>> GEM_BUG_ON(gt->awake);
>>>>
>>>> intel_uc_suspend(&gt->uc);
>>>> + intel_pxp_suspend(&gt->pxp);
>>>>
>>>> /*
>>>> * On disabling the device, we want to turn off HW access to memory
>>>> @@ -355,7 +356,7 @@ void intel_gt_suspend_late(struct intel_gt *gt)
>>>>
>>>> void intel_gt_runtime_suspend(struct intel_gt *gt) {
>>>> - intel_pxp_suspend(&gt->pxp, true);
>>>> + intel_pxp_runtime_suspend(&gt->pxp);
>>>> intel_uc_runtime_suspend(&gt->uc);
>>>>
>>>> GT_TRACE(gt, "\n");
>>>> @@ -373,7 +374,7 @@ int intel_gt_runtime_resume(struct intel_gt *gt)
>>>> if (ret)
>>>> return ret;
>>>>
>>>> - intel_pxp_resume(&gt->pxp);
>>>> + intel_pxp_runtime_resume(&gt->pxp);
>>>>
>>>> return 0;
>>>> }
>>>> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
>>>> b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
>>>> index 23fd86de5a24..3f91996dc6be 100644
>>>> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
>>>> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
>>>> @@ -7,8 +7,9 @@
>>>> #include "intel_pxp_irq.h"
>>>> #include "intel_pxp_pm.h"
>>>> #include "intel_pxp_session.h"
>>>> +#include "i915_drv.h"
>>>>
>>>> -void intel_pxp_suspend(struct intel_pxp *pxp, bool runtime)
>>>> +void intel_pxp_suspend_prepare(struct intel_pxp *pxp, bool runtime)
>>>> {
>>>> if (!intel_pxp_is_enabled(pxp))
>>>> return;
>>>> @@ -23,10 +24,18 @@ void intel_pxp_suspend(struct intel_pxp *pxp, bool
>>> runtime)
>>>> */
>>>> if (!runtime)
>>>> intel_pxp_invalidate(pxp);
>>>> +}
>>>>
>>>> - intel_pxp_fini_hw(pxp);
>>>> +void intel_pxp_suspend(struct intel_pxp *pxp) {
>>>> + intel_wakeref_t wakeref;
>>>>
>>>> - pxp->hw_state_invalidated = false;
>>>> + if (!intel_pxp_is_enabled(pxp))
>>>> + return;
>>>> + with_intel_runtime_pm(&pxp_to_gt(pxp)->i915->runtime_pm,
>>> wakeref) {
>>>> + intel_pxp_fini_hw(pxp);
>>>> + pxp->hw_state_invalidated = false;
>>>> + }
>>>> }
>>>>
>>>> void intel_pxp_resume(struct intel_pxp *pxp) diff --git
>>>> a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
>>>> b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
>>>> index c89e97a0c3d0..f2cf3117ed93 100644
>>>> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
>>>> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
>>>> @@ -9,10 +9,15 @@
>>>> #include "intel_pxp_types.h"
>>>>
>>>> #ifdef CONFIG_DRM_I915_PXP
>>>> -void intel_pxp_suspend(struct intel_pxp *pxp, bool runtime);
>>>> +void intel_pxp_suspend_prepare(struct intel_pxp *pxp, bool runtime);
>>>> +void intel_pxp_suspend(struct intel_pxp *pxp);
>>>> void intel_pxp_resume(struct intel_pxp *pxp); #else -static inline
>>>> void intel_pxp_suspend(struct intel_pxp *pxp, bool runtime)
>>>> +static inline void intel_pxp_suspend_prepare(struct intel_pxp *pxp,
>>>> +bool runtime) { }
>>>> +
>>>> +static inline void intel_pxp_suspend(struct intel_pxp *pxp)
>>>> {
>>>> }
>>>>
>>>> @@ -20,5 +25,14 @@ static inline void intel_pxp_resume(struct
>>>> intel_pxp *pxp) { } #endif
>>>> +static inline void intel_pxp_runtime_suspend(struct intel_pxp *pxp) {
>>>> + intel_pxp_suspend_prepare(pxp, true);
>>>> + intel_pxp_suspend(pxp);
>>>> +}
>>>>
>>>> +static inline void intel_pxp_runtime_resume(struct intel_pxp *pxp) {
>>>> + intel_pxp_resume(pxp);
>>>> +}
>>> For the casual reader, the pxp suspend/resume functions have become an
>>> impossible interface to use correctly without digging into the source code.
>>>
>>> Separate runtime suspend/resume calls *and* a suspend function with
>>> runtime parameter?!?
>> Hi Daniele, would you be ok if I add runtime arg? Please let me know what do you think.
> Err, please *avoid* having runtime as parameter.
>
> BR,
> Jani.

Might be better to just open-code the runtime_suspend function, i.e.:

void intel_pxp_runtime_suspend(struct intel_pxp *pxp)
{
if (!intel_pxp_is_enabled(pxp))
return;

pxp->arb_is_valid = false;
pxp->hw_state_invalidated = false;

intel_pxp_fini_hw(pxp);
}

And remove the bool param from suspend_prepare. No changes required for
the resume.
Note that the change above requires the function to be moved to the C
file, with an empty implementation to be added in the header for when
the PXP config is not set (basically the same thing we do for the
pxp_suspend function).

Daniele

>
>> Thanks,
>> Tejas
>>> BR,
>>> Jani.
>>>
>>>> #endif /* __INTEL_PXP_PM_H__ */
>>> --
>>> Jani Nikula, Intel Open Source Graphics Center